Scientists have known for quite awhile now that rats are highly sociable and regularly help each other out. Now the results of a new study have shown that a rat just has to smell another rat that is engaged in helpful behavior to increase their own helpfulness. This is the first study to show that just the smell of a cooperating rat is enough to trigger a helpful response.
Researchers carried out a series of tests to study the importance of the scent of a rat while making cooperative decisions. The rats being studied could choose to help another rat by pulling a platform containing a reward towards the other rat’s cage. This provided food for the other rat but did not have any immediate benefit for them personally. The researchers then provided the test rats either with the smell of a rat that was being helpful to another rat in a different room or with the smell of a rat that was not engaged in helpful behavior. The researchers were surprised to find that just the scent of a rat engaged in helpful behavior was enough to illicit helpful behavior in the other.
“Test rats increased their own helping behavior when they were presented with the smell of a helpful rat. Remarkably, this holds true even though they did not experience this helpful behavior themselves.”
-Dr. Nina Gerber, researcher, Wildlife Sciences, University of Göttingen
Journal Reference: Nina Gerber, Manon K. Schweinfurth, Michael Taborsky. The smell of cooperation: rats increase helpful behaviour when receiving odour cues of a conspecific performing a cooperative task. Proceedings of the Royal Society B: Biological Sciences, 2020; 287 (1939): 20202327. DOI: 10.1098/rspb.2020.2327